Osmium concentration and isotopic composition of North Pacific deep-sea sediments, supplement to: Esser, Bradley K; Turekian, Karl K (1988): Accretion rate of extraterrestrial particles determined from osmium isotope systematics of Pacific Pelagic clay and manganese nodules. Geochimica et Cosmochimica Acta, 52(6), 1383-1388

DOI

Pelagic clay and Mn nodules from DOMES sites in the North Pacific and a varved glacial lake deposit from Connecticut were analysed for Os concentration and isotopic composition by isotope-dilution secondary ion mass spectrometry after treatment by NiS fusion or oxalic acid leaching. Bulk pelagic clay from DOMES site C has 187Os/186Os = 6.5 and Os = 0.14 ng/g. Oxalic acid leaches of this same sediment and of Mn nodules from DOMES sites A and C have more radiogenic 187Os/186Os ratios which average 8.3. Bulk glacial Lake Hitchcock sediment has 187Os/186Os = 12.5 and Os = 0.06 ng/g. The total Os flux to North Pacific pelagic clay is 7 to 10 ng Os/cm2/106 y. Lake Hitchcock sediment provides an integrated value for the local crustal 187Os/186Os ratio. The oxalic acid leaches are assumed to attack hydrogenous phases selectively. A simple model in which the only sources of Os to the ocean are continental crust with the isotopic composition of Lake Hitchcock (187Os/186Os = 12.5) and extraterrestrial particles with 187Os/186Os = 1.1 results in a cosmic flux of osmium to the sediment of 4.9 ng Os/cm2/106 y of which 20% is hydrogenous. A model in which the sources of Os to the ocean are continental crust with an 187Os/186Os ratio of 30 (from the model of Palmer and Turekian, 1986), oceanic mantle or crust with 187Os/186Os = 1.04 and extraterrestrial particles with 187Os/186Os = 1.1 results in a cosmic flux of Os to the sediment of 5.7 ng Os/cm2/106 y of which none is hydrogenous. These extraterrestrial Os fluxes correspond to maximum C-1 chondrite accretion rates of between 4.9 × 104 and 5.6 × 104 tonnes/y.

Identifier
DOI https://doi.org/10.1594/PANGAEA.880007
Related Identifier https://doi.org/10.1016/0016-7037(88)90209-8
Related Identifier https://doi.org/10.7289/V52Z13FT
Related Identifier https://doi.org/10.7289/V53X84KN
Metadata Access https://ws.pangaea.de/oai/provider?verb=GetRecord&metadataPrefix=datacite4&identifier=oai:pangaea.de:doi:10.1594/PANGAEA.880007
Provenance
Creator Esser, Bradley K; Turekian, Karl K
Publisher PANGAEA - Data Publisher for Earth & Environmental Science
Publication Year 1988
Rights Creative Commons Attribution 3.0 Unported
OpenAccess true
Representation
Language English
Resource Type Supplementary Collection of Datasets
Format application/zip
Size 2 datasets
Discipline Earth System Research
Spatial Coverage (-151.285W, 9.038S, -125.907E, 15.327N)
Temporal Coverage Begin 1975-10-29T00:00:00Z
Temporal Coverage End 1975-11-13T00:00:00Z